Companies are now using insurers and employee wellness firms to mine data about employees' prescription drugs and shopping habits to predict workers' healthcare needs.
This practice has been used in the United States by the likes of Walmart to send specifically targeted health-related advice to employees.
Harry Greenspun from Deloitte LLP's Centre for Health Solutions told the Wall Street Journal: "I bet I could better predict your risk of a heart attack by where you shop and where you eat than by your genome."
This data trawling can now used to find out if female workers are pregnant or trying to conceive.
Healthcare information company, Castlight, have launched a new product which uses insurance claims to check if women have stopped birth control prescriptions.
The product will match such information with the age of the woman and that of her children to find out the likelihood of a imminent pregnancy.
Castlight's chief research and development officer, Jonathan Rende said this information would trigger emails to the female employee in question offering advice on choosing an obstetrician and prenatal care.
Critics have attacked such use of employee data stating it could impinge on workers' health privacy.
University of Maryland law professor, Frank Pasquale, said: "There are enormous potential risks in these efforts, such as the exposure of personal health data to employers or others."
